House and Senate candidates raised a record $284 million as the elections entered their final stretch in mid-October, Common Cause, the self-styled citizens' lobby, reported yesterday.

Nearly 29 percent of the money, $81.9 million, came from political action committees. Two years ago, PAC receipts at the same point totaled $66.5 million, or about 28 percent.

The candidates spent $231.6 million by Oct. 17, and had $60.6 million left for the last three weeks of the campaign.

The Common Cause report said that receipts rose faster than expenditures since mid-October 1982. Fund raising for House and Senate candidates rose 19 percent over the 1982 total of $239.1 million, while spending increased 9 percent over the 1982 level of $211.9 million.

House candidates, the study showed, took considerably more money from PACs than did Senate candidates. Contributions from PACs accounted for 36.3 percent of the money raised for House contests, but 19.2 percent of the Senate war chests.

Candidates in House races, Common Cause also found, were holding onto 56 percent more cash going into the final weeks than their counterparts did in 1982. And House incumbents are holding onto most of the money, retaining $42.7 million or 91 percent of the $46.9 million in cash on hand reported as of Oct. 17.

Rep. James Jones (D-Okla.), chairman of the House Budget Committee, raised the most -- $1,224,306 -- for a House race, and he got more of that from PACs -- $585,330 -- than did any other House candidate.

Forty-six House candidates, all incumbents, received $200,000 or more from PACs, Common Cause said. A total of 148 incumbents, including 18 committee chairmen and party leaders, got 50 percent or more of their funds from PACs, while only 17 challengers and three open-seat candidates received that high a proportion.

In the Senate races, Rep. Phil Gramm (R-Tex.) and Sen. Charles H. Percy (R-Ill.) each collected more than $1 million in PAC contributions.

Top House fund-raisers after Jones were Manhattan Borough President Andrew Stein (D-N.Y.) with $1,176,199, and Rep. Bruce Morrison (D-Conn.), $887,395.

Democrats also were the biggest spenders in House races so far, led by Stein who had paid out $1,083,782; Jones, $882,383; and Rep. Joseph Addabbo (D-N.Y.), $848,670. Stein's opponent in New York's silk stocking district, Rep. Bill Green (R), was in fourth place on the spending list with $700,993.

Total 1983-84 House fund-raising as of Oct. 17 was $159.6 million, or 10 percent more than for the comparable period in 1982. But total spending dropped by 4 percent, from $127.4 million in 1982 to $121.9 million this time.

In Senate contests, fund raising and spending both went up sharply. The 65 candidates for the Senate collected $124.3 million, or 32 percent more than in 1982, through Oct. 17, and they had spent $109.7 million, a 34 percent increase.

The top Senate fund-raiser in 1982 was Sen. Pete Wilson (R-Calif.) with $7.2 million. Four Senate candidates already have topped that -- Sen. Jesse Helms (R-N.C.), with $14.4 million; Gov. Jay Rockefeller (D-W.Va.), $9.4 million; North Carolina Gov. James B. Hunt Jr., $8.6 million; and Gramm, $7.9 million.

By mid-October, the same four men also had surpassed the 1982 spending record of $7.17 million set by Minnesota Democratic candidate Mark Dayton.

Spending in the Hunt-Helms race in North Carolina, by far the most expensive congressional contest in history, totaled $21.7 million. The Texas battle between Gramm and state Sen. Lloyd Doggett (D-Tex.), was next, costing $12 million. The West Virginia race between Rockefeller and John Raese (R) ranked third with more than $10 million in expenditures, and all but $765,425 of that was Rockefeller's money.