Enviro group ups spending to unseat Mass. Sen. Brown

The mailer, along with a more than $700,000 canvassing initiative, will likely push the group’s spending on the race over the $1 million mark, Nayak said.

LCV’s political action arm has spent more than $5 million so far in this election cycle, already topping its 2010 total, Nayak said.

It has backed Democrats Warren, Rep. Martin HeinrichMartin HeinrichThis Week in Cybersecurity: Dems press for information on Russian hacks Overnight Cybersecurity: Last-ditch effort to stop expanded hacking powers fails Intel Dems push for info on Russia and election be declassified MORE (N.M.), former Virginia Gov. Tim KaineTim KaineTrump adviser: Sanders would have made for tougher race as Clinton's VP Trump adviser: Clinton/Sanders ticket would've been tougher to beat Terry McAuliffe: Clinton likely done with politics MORE, Rep. Chris MurphyChris MurphyWrestling mogul McMahon could slam her way into Trump administration Dem on Trump's foreign policy moves: 'That's how wars start' House passes medical cures bill MORE (Conn.) and Sen. Jon TesterJon TesterRed-state Dems face tough votes on Trump picks Montana Republican warns of Senate challenge to Tester Vulnerable Dems ready to work with Trump MORE (Mont.).

Last week, LCV opened up a six-figure campaign against Murphy’s Republican opponent, Linda McMahon. The group also spent $850,000 on a direct-mail effort in Virginia that aims to paint Kaine’s rival, former Sen. George Allen (R-Va.), as a pawn of Big Oil.

The group also has spent $1.5 million on House races attempting to unseat five GOP lawmakers it has dubbed the “Flat Earth Five.” That campaign targets Reps. Ann Marie Buerkle (N.Y.), Dan BenishekDan BenishekRepublican groups launch final ad blitz in key House battlegrounds Tea Party class reassesses record Michigan Republican to retire MORE (Mich.), Dan Lungren (Calif.), Quico Canseco (Texas) and Joe Walsh (Ill.).

Nayak said such endeavors would continue through the Nov. 6 election.

“Absolutely,” he said. “We continue to see really stark contrasts between the candidates on our issues in these elections.”

Nayak said he hopes the 150,000 people reached through the mailer will make it “very hard for them to even consider voting for Scott Brown.”

The mailer will emphasize Brown’s vote to sustain oil industry tax breaks, which Nayak said is out of step with most Massachusetts voters.

Nayak noted that a higher turnout is expected in a presidential election year compared with the special election Brown won to replace the late Sen. Ted Kennedy (D-Mass.). He said the mail campaign is necessary to familiarize more of the state’s voters with Brown’s positions and record.

The Hill rates the Massachusetts race as a “toss-up.”