The ad, released by Patriot Majority USA and Senate Majority PAC, follows a poll released Tuesday by Senate Conservatives Fund that shows Pryor to be vulnerable against Cotton.

The poll, conducted by Basswood Research, gives Pryor 41 percent support to Cotton's 40 percent support. The Republican polling firm surveyed 600 likely Arkansas voters from June 22-23 and has a margin of error of plus or minus 4 percentage points.

However, that's a significant improvement for Pryor since the last GOP poll conducted by Basswood for the Club for Growth and Senate Conservatives Fund (SCF), in March. That survey showed Pryor taking 35 percent to Cotton's 43 percent support.

Pryor is a top target for Republicans, who believe him to be vulnerable due to President Obama's unpopularity in the state. The SCF poll indicated 40 percent of respondents believe Pryor sides too much with Obama and "liberals in Congress," while 38 percent don't agree.

SCF previously spent $400,000 on an ad campaign that characterized him as too liberal.

But Democrats are coming to Pryor's aide, attempting to preempt Cotton's potential bid with a new ad that characterizes him as too focused on national spotlight and not enough on Arkansans.

"Tom CottonThomas (Tom) Bryant CottonDOJ probing Huawei over possible sanctions violations: report The Hill's Morning Report - Lawsuits, investigations send Trump on Twitter tirade GOP senator: Democratic opposition to Pompeo 'driven 100 percent by politics' MORE: Just elected and already seeking the national limelight -- behind the glitz Cong. Cotton forgot about us," a narrator says.

The ad notes Cotton's support for the Ryan budget and suggests that he's voted to give Congress "taxpayer-funded healthcare for life," a reference to attempts to repeal the healthcare reform law.

It's backed by a $270,000 buy and will run statewide over the next two weeks. Though Cotton hasn't yet entered the race, the early attack on his record is an indication from Democrats that they're planning to fight heavily to keep the seat — one of a handful in difficult red states that they'll need to retain if they hope to keep control of the Senate in 2014.

Watch the ad: