San Francisco -- Former President Bill Clinton, one of the Democrats' most reliable designated hitters in political fundraising, will head to California next month to bat for two of his party's candidates facing tough challenges in November -- Jerry Brown and Gavin Newsom. Clinton, who visited California more than 70 times during his two terms as president, will campaign for state Attorney General Brown, who is running for governor, and San Francisco Mayor Newsom, who is running for lieutenant governor, on Oct. 15 and 17 in Northern and Southern California, the party announced Friday. With fewer than 50 days until the Nov. 2 general election, the announcement of Clinton's visit highlights the party's election challenges this year -- even in blue-leaning California, where Democrats hold a 2.3 million-voter advantage over Republicans. In the race to succeed Republican Gov. Arnold Schwarzenegger, Brown has struggled to keep even with Republican Meg Whitman, the former eBay CEO who has put $119 million of her own money into her campaign -- the most ever by a political candidate, surpassing the $110 million New York Mayor Michael Bloomberg gave his campaign last year. Newsom has a slight lead over Lt. Gov. Abel Maldonado, a moderate Republican appointed this year by Schwarzenegger and one of the highest-ranking Latino Republicans ever in the state. Clinton's visit to California will give him a chance to showcase the gap between Republicans and Democrats on issues dear to his heart -- green technology and climate change. Brown and Newsom oppose Proposition 23, a measure on the November ballot that would suspend AB32, the state's landmark law to curb greenhouse gases, until the state unemployment rate drops to 5.5 percent for four consecutive quarters. Texas-based oil companies have contributed heavily to the campaign for the initiative. California Republican candidates, including Whitman and Carly Fiorina, who is challenging Sen. Barbara Boxer, call AB32 a job killer. Fiorina supports Prop. 23, while Whitman and Maldonado have said they are leaning toward opposing it but have not taken a position. Clinton's visit seems to put to rest a long-running feud between he and Brown that dates back to the 1992 presidential primary, where they competed for their party's nomination. The feud was rekindled this month, when Whitman used footage from the Clinton-Brown debate that year, during which Clinton attacked Brown for raising taxes as governor. In response to Clinton's remark in the Whitman ad, Brown was captured this week on video making what he later called an 'inappropriate' joke about Clinton's veracity. Brown apologized to the former president on Monday, and Clinton endorsed Brown the next day, saying he made his 1992 charge against Brown based on a story that he now knows contained faulty data. Independent analysts have confirmed that the news story Clinton quoted from in the debate erroneously included information on California income tax rates from the year before Brown took office in 1975. Whitman has refused Brown's request to withdraw the ad. Pressed by employees of social networking and review site Yelp this week in San Francisco, Whitman calling the spot 'essentially' true. Libertarian blogger and political strategist Patrick Dorinson, who was Brown's finance director before he went to work for Clinton's 1992 presidential campaign, said Clinton's visit will be valuable for Democrats -- but may do only limited good for Brown's effort. 'Clinton's a great campaigner. But all he's going to do is remind people why they liked Bill Clinton; and Jerry's still Jerry,' said Dorinson, who writes the cowboylibertarian.com blog. While the Brown and Clinton camps are 'kissing and making up now,' Dorinson said, 'I guarantee you' that Whitman's campaign 'has a whole passel of stuff' Brown has said about Clinton on air, from Brown's 'We the People' radio program in the Bay Area in the 1990s to talk shows such as CNN's Larry King Live. 'Wait until Clinton gets here,' Dorinson added. 'That's when Whitman will dump the house' on Brown. 'You think the wicked witch of the West dumped a house on Dorothy? You ain't seen nothin' yet.' 