A conservative group run by political operatives aligned with former Vice President Mike Pence has launched a new advertising campaign to defeat President Joe Biden’s $2 trillion social spending bill as Democrats race to pass the legislation before year’s end.

The Coalition to Protect American Workers is airing $1.2 million worth of television ads targeting key Democratic centrists, including Rep. Jared Golden of Maine and Sen. Jon Tester of Montana, whose votes are considered uncertain. House Speaker Nancy Pelosi of California has vowed her chamber will not break for Thanksgiving until Biden’s “Build Back Better” legislation is sent to the Senate for consideration.