With just three weeks remaining before mail-in ballots go out for the November election, the political battle is intensifying over Mountain View's proposed rent-control measures.

In recent days, landlord and business groups have mounted an aggressive campaign against Measure V, the citizen-backed measure being spearheaded by the Mountain View Tenants Coalition. In contrast, these groups are showing a lukewarm response to Measure W, the council's milder rent-stabilization alternative.

The chief opposition group, the California Apartment Association, in recent days disclosed in campaign filings it had collected more than $520,000 from various landlords and interest groups across to state to help oppose Measure V, as well as similar Bay Area rent-control proposals in Alameda, Burlingame, Richmond and San Mateo.

In the same filings, CAA officials reported they would spend $95,000 on polling, television advertising and mailers in Mountain View to help defeat Measure V. Large donors helping the CAA in its campaign include Prometheus Real Estate Group and development firms scattered across the state. The campaign also received $40,000 from the Mountain View Housing Council, a local political action committee that dates back to at least 2008, according to city records.

The apartment association did not report any expenditures or fund-raising directed toward opposing Measure W.

Mountain View voters will have a choice between two ballot measures designed to curb rising apartment rents. Measure V, put forward by the Mountain View Tenants Coalition, would amend the city charter to prohibit no-cause evictions and tie rent increases to the rise in the regional Consumer Price Index. When Measure V supporters gathered enough signatures to put it on the ballot, the City Council drafted Measure W as an alternative. Measure W would create a binding-arbitration system to settle disputes between landlords and tenants, as well as create a package of financial disincentives to discourage evictions.

In recent days, the Mountain View Chamber of Commerce has come out strongly against Measure V. In a newsletter sent out earlier this week, the business association strongly urged its members to vote against the Tenants Coalition's measure, describing it as an "ineffective" policy that would ultimately reduce the rental housing stock in Mountain View.

The Chamber's board of directors had met repeatedly over recent weeks to deliberate over which local election issues to support, including the rent-control proposals, said Chamber CEO Tony Siress. The response to the Measure V charter amendment was unequivocal -- all 17 board members voted to oppose it. Meanwhile, the Chamber's reaction to the city's Measure W was basically a tie, meaning the group won't take any position on it, Siress said.

Summing up his group's stance, Siress said Measure V would make rent-control a permanent policy of Mountain View even though the current housing crisis is a temporary situation. As a policy, rent-control would effectively encourage property owners to forgo maintenance and exit the Mountain View market, he warned.

"A charter amendment to enforce rent control defies the basic core of economics," he said. "The goal of rent control is never resolved and in time the problem gets worse and bigger."

The Tenants Coalition doesn't agree with that assessment of its ballot measure. When shown the Chamber's newsletter by the ==I Voice, the group's spokesman Daniel DeBolt described the wording as misleading, verging on "fear-mongering".

"The Chamber's opposition to Measure V is unfortunate because extreme rent increases are making it hard for local businesses to hire and retain experienced employees," he said "Experienced employees, nurses, paramedics, caregivers, teachers and hard working families can't afford skyrocketing rents."

Email Mark Noack at mnoack@mv-voice.com