Sen. Mark Kirk (R-IL), a vulnerable Republican senator in a tough re-election fight against Rep. Tammy Duckworth (D-IL), says that his efforts to separate his campaign from Donald Trump’s presidential run have paid off.

“It’s helped because I’m a very independent voice for Illinois,” Kirk told CNN in an interview published on Monday.

In June, Kirk ran a television ad arguing that Trump is “not fit to be commander in chief” and highlighting the Republican senator’s calls for a vote on President Obama’s Supreme Court nominee.

The Kirk campaign told CNN that since running the ad, the campaign has seen an increased interest in their campaign.

When asked if he would win in November without backing Trump, Kirk told CNN, “I have always run way ahead of my ticket.”