Steve Hilton and Chad Bianco give the GOP two of its most prominent candidates in years, signaling a heightened sense of opportunity for the party. But the odds remain steep.

After relocating to California in 2012, Steve Hilton embraced the American entrepreneurial spirit by co-founding Crowdpac.com, a Silicon Valley tech startup. His growing presence in conservative media eventually earned him his own Fox News Channel show, The Next Revolution, which aired Sunday nights from 2017 to 2023.

Mr. Hilton is the second prominent Republican to enter the wide-open race. He faces difficult odds in the Democratic-led state.