** Wall Street brokerages start coverage of Republican Party's top bank, Chain Bridge Bancorp , on a bullish note on Tuesday as IPO research quiet period ends

** Piper Sandler starts coverage with "overweight" rating and $27 PT, a 27.7% upside to stock's last close

** Says political deposit niche is attractive and has healthy growth potential given the opportunity is even larger if one were to count state elections

** Nation's largest banks have largely ceded this business because of concerns about reputational risk - Piper Sandler

** Raymond James start coverage with a "strong buy" rating and $29 PT, a 37% upside to stock's last close

** Says the "800-lb elephant" of campaign finance will continue to demonstrate low-cost deposit growth from its niche business, driving continued strong profitability

** Piper Sandler, Raymond James, and Hovde Group were the underwriters for the IPO

** As of last close, CBNA stock down 3.9% since debut on Oct. 4

(Reporting by Arasu Kannagi Basil in Bengaluru)

((ArasuKannagi.Basil@thomsonreuters.com;))