Former President Barack Obama threw his support behind Democrat Angela Alsobrooks on Friday, headlining a new ad in which he praises her record and echoes the party’s message that the U.S. Senate majority could be determined by the outcome of her race in Maryland.

Alsobrooks released the 30-second spot as both she and Republican Larry Hogan entered the final three-week stretch before early in-person voting and almost four weeks until Election Day.

Both candidates and their allies are stepping up their advertising blitzes in a rare competitive race in a state that has not elected a Republican to the Senate since 1980.

This year, Obama says in the ad, “Control of the Senate could come down to Maryland.”

The former president hits other broad points in a quick pitch that mirrors Alsobrooks’ top campaign themes.

“As state’s attorney, she helped cut violent crime in half. And in the Senate, Angela will fight for you,” Obama says. “She’ll work to lower costs and lead the fight to protect our democracy and our freedoms.”

Alsobrooks spoke shortly before both Michelle and Barack Obama in primetime during the second night of the Democratic National Convention in Chicago this summer. She’s also received high-profile assistance from Vice President Kamala Harris, a mentor and longtime friend to her, with two joint appearances in the state in June.

That stands in contrast with Hogan, who has pledged to be an independent voice in the Senate and routinely denounced Republican Donald Trump as his party’s leader. He rejected Trump’s endorsement of him and said he will not vote for the former president again this year.

Hogan is, however, receiving a strong backing from other Republicans who want to see him join their ranks in Washington, D.C. He’s held fundraisers with Republican senators and a super PAC seeded with money from a major Republican donor recently scheduled at least $18.3 million in ad time to promote his candidacy.