The new acquisition proposal for AdTheorent at $3.35 per share in cash could potentially increase investor interest and drive up the stock price in the short term. This is because the offer provides a clear alternative to the existing merger deal with CadOnt, potentially leading to a bidding war or a reevaluation of the company's value. However, the final impact on the stock price will depend on the details of the proposal, the response from CadOnt, and the perception of AdTheorent's future prospects by the market.