Ten RIA firms with combined assets of $6.1 billion merged or were acquired in the third quarter of 2012, but seven were acquired by two consolidators, according to Schwab Advisor Services.

Jon Beatty, senior vice president of sales and relationship management at Schwab, said uncertainty about the financial markets and the upcoming presidential election led to a modest decline in M&A activity during the period. But firms active in the RIA market report that number of discussions, or instances of "romancing," are near an all-time high.

Regardless of who emerges as the victor in November, one acquirer said he expects a noticeable surge in completed transactions in the fourth quarter. Uncertainty over an increase in the capital gains tax rate and the strong performance of U.S. equity markets in the third quarter should contribute to this increase, he added.

National acquiring firms accounted for seven of the 10 deals completed in the third quarter. Many of these transactions included wirehouse brokers leaving their firms to join a United Capital or a Hightower Advisors type of consolidator.

"While national acquiring firms remain dominant players, RIAs as acquirers have been sitting on the sidelines waiting for the right opportunity,"  Beatty said. "The general economy is weighing on everyone's minds and we don't have a spark."

For the first three quarters of 2012, there have been 19 transactions representing $42.3 billion in assets, approaching last year's total of $43.9 billion in assets for the full year of 2011.