Senate races

Sen. Claire McCaskill (D-Mo.) is launching a new television advertisement touting her work on behalf of veterans.

McCaskill's reelection campaign wouldn't provide details of the ad buy, but a Republican source told The Hill that McCaskill's campaign has booked $352,000 worth of airtime in Missouri markets for a two-week period starting Monday.

The ad highlights McCaskill's work to investigate the mishandling of graves at Arlington National Cemetery and legislation she pushed to address the mismanagement.

"Waste, fraud, the ultimate abuse," says the narrator in the ad. "So Claire McCaskill passed new laws to toughen oversight and hold the bureaucrats accountable. Because when heroes are laid to rest, the least they deserve is a senator who never will."

The ad is part of a major push by McCaskill to boost her appeal among veterans and national security hawks as she seeks reelection in a state where voters are down on Democrats and President Obama.

Rick Santorum endorsed Texas Senate candidate Ted Cruz Thursday afternoon, just minutes after a new poll showing his main rival, Texas Lt. Gov. David Dewhurst (R), nearing the 50 percent threshold he needs to avoid a runoff election.

Sen. Sherrod Brown’s (D-Ohio) lead over Republican Josh Mandel has expanded slightly, and his margin is back into the double digits, according to a poll released Thursday.

Brown leads Mandel by 14 points in the NBC-Marist poll, besting the first-term state treasurer 51-37. Twelve percent were undecided.

When NBC-Marist polled the race in March, Brown had a 10-point advantage on Mandel. But a Quinnipiac University poll in early May and other surveys from both Democratic and Republican firms had showed Mandel narrowing the gap to just a handful of points.

Both candidates have been flooding the airwaves with television ads — mostly negative — although most of the spending by super-PACs in the race has benefited Mandel.

Two new polls released Thursday showed Rep. Connie Mack (R-Fla.) gaining ground in match-ups with Florida Sen. Bill Nelson (D).

An NBC-Marist poll showed Nelson 4 points ahead of Mack, beating out the front-running Republican 46-42.

And a Quinnipiac University poll put the race in a dead heat, with Mack leading Nelson 42-41 — within the margin of error.

That poll also showed Mack maintaining a dominant lead in the primary, where he takes 40 percent to 7 for former Sen. George LeMieux (R-Fla.) and 8 for Tea Party favorite Mike McCalister.

Former Virginia Gov. Tim Kaine (D) leads former Sen. George Allen (R-Va.) by 6 percentage points, according to a new poll from NBC News.

The poll has Kaine leading Allen by 49 percent to 43, his largest lead in any survey for months, although NBC's last poll of the race, in early March, had him up 9 points while others showed it much closer. The two are locked in a tight battle for retiring Sen. Jim Webb's (D-Va.) open seat.

The same poll had President Obama leading Mitt Romney by 48 percent to 44. Virginia is a crucial swing state for both the presidential race and control of the Senate, and since Kaine and Allen are so well-known there it is unlikely to see much movement in the polls without a major event between now and Election Day.

Kaine will have some big help Thursday: Vice President Joe Biden will head to northern Virginia to headline a fundraiser for him.

The poll was conducted from May 17-20 and has a margin of error of plus or minus 3 percent.

This post was updated at 11:50 a.m.

Former Texas Solicitor General Ted Cruz (R) has loaned his campaign $400,000 for the stretch run of his Senate primary campaign, according to the Dallas Morning News, a sign that he's worried he needs to spend to ensure he makes the runoff election against Texas Lt. Gov. David Dewhurst (R).

The multimillionaire Dewhurst and a super-PAC backing him have spent more than $10 million on the race, approximately five times more than Cruz and his allies have raised and spent. Cruz, a Tea Party favorite, hopes that if he can force a runoff and get a clear one-on-one shot against Dewhurst he can catch up with him in the second round of voting.

There have been no recent credible public polls, but Dewhurst's internal polls show he's close to the 50 percent mark needed to avoid a runoff, while both Cruz and Dallas Mayor Tom Leppert contend Dewhurst is far below that mark.

Polls show Scott Brown and Elizabeth Warren locked in a dead heat, and most say her ancestry issue is moot.

Former Alaska Gov. Sarah Palin (R) has endorsed Sen. Orrin Hatch (R-Utah), who is facing a Tea Party challenge from former state Sen. Dan Liljenquist (R).

Democrat Elizabeth Warren is locked in a dead heat with Sen. Scott Brown (R-Mass.), according to a poll released Tuesday and commissioned by the Democratic Senatorial Campaign Committee (DSCC).

Warren and Brown each took 46 percent in the poll by Democratic firm Harstad Strategic Research.

Multiple polls over the past few months have suggested the race is tied. But Republicans have been hoping that a major flap over Warren's claim to Native American heritage would nudge the numbers in Brown's direction.

A major anti-abortion rights group endorsed Republican Deb Fischer, the rural rancher and Nebraska state senator who pulled off an upset victory last week in the state's GOP Senate primary. Read more...