The Providence City Council is holding a rare Friday evening meeting as it attempts to override Mayor Brett Smiley’s veto of its rent-control ordinance, but there is no sign that it has secured the 10 votes it needs to force the proposal into law.

It’s a high-profile political test for Council President Rachel Miller, who appears to see upside either way: enact rent control now by flipping a vote – she has nine votes – or use a narrow defeat to rally supporters and expand her coalition in September’s Democratic primary. 

Rent control is also a centerpiece of state Representative David Morales’ campaign for mayor against Smiley, and a failure to override the veto is likely to galvanize progressives who think he has a chance at unseating the incumbent.

The bigger picture: Behind the scenes, there has been an effort to pressure one of the six “no” votes on rent control to switch sides, with Ward 1 Councilman John Goncalves being threatened with a Democratic primary challenger in September and Ward 7 Councilwoman Ana Vargas under fire for accepting an unusually large amount of donations from landlords.

Goncalves represents Fox Point, Wayland Square, College Hill, and downtown – neighborhoods where progressive energy collides with a more cautious strain of East Side liberalism – leaving him to navigate a debate that has increasingly become a progressive litmus test, even as he argues the policy deserves more study. 

Vargas, who represents parts of Silver Lake and the Hartford neighborhood, now finds herself caught in the kind of hyper-engaged City Hall battle that can overwhelm newer council members unaccustomed to having every donor, vote, and public statement dissected. 

Keep in mind that every member of the Providence City Council is a Democrat, but City Hall is still full of rival factions and shifting alliances that can form around anything from rent control to who gets credit for a neighborhood carnival. 

My colleague Steph Machado will have full coverage of the 6 p.m. vote at Globe.com/RI.