A conservative organization just launched a new ad campaign targeting vulnerable Republicans in the Senate and demanding that they speak out against President Donald Trump.

The spot from Republicans for the Rule of Law features a quote from Vice President Mike Pence, who said during the 2016 campaign that “foreign governments cannot participate in the American political process.”

But as the ad points out, Trump asked both Ukraine and China for dirt on former Vice President Joe Biden, who is running for the Democratic presidential nomination.