The CPS is considering files sent by police following investigations in up to 27 constituencies.
It relates to claims some campaigning costs in the 2015 general election were wrongly recorded.
The Conservative Party has insisted administrative errors were to blame rather than any intention to deceive.
And it has said some of the spending was correctly declared.
It is alleged the Conservatives spent tens of thousands of pounds on local campaigns - including on "battle bus" visits by activists - which were either not declared or were wrongly registered as national spending.
The allegations came to light following an investigation by Channel 4 News.
Under complex election spending rules, parties must disclose national spending separately from money used to promote each candidate, and separate national and local limits apply.
Up to 16 police forces across England have submitted files to be considered by prosecutors.
The CPS will consider whether there is sufficient evidence of a breach in the law, and whether a prosecution is "in the public interest".
If general election candidates are prosecuted the Conservative Party will have to decide whether to suspend them and replace them as nominees.
The last date for candidates to register for the election is 11 May.
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Allan Bell made the statement during peaceful demonstrations by pro-choice and anti-abortion campaigners outside the Manx parliament on Tuesday.
Mr Bell said work on changing the legislation would begin "at the end of this year, early next year".
The Termination of Pregnancy Act 1995 is the current law governing abortions in the Isle of Man.
This means a termination can only be carried out on the island in the case of a pregnancy arising from a criminal offence such as rape, or on mental health grounds.
For most women seeking an abortion, the only option is to travel to the UK to pay for the procedure.
Manx campaign group, CALM (Campaign for Abortion Law Modernisation), which was established in April, wants island legislation to be brought in line with the UK.
Although it is not currently illegal, the group said it is "almost impossible" for women to have a termination on the Isle of Man.
A spokesman added: "The current act is incredibly restrictive. We are not saying abortion should be available to everyone at the drop of a hat."
Anti-abortion campaigners at the rally held banners saying: "Thou shalt not kill".
A spokesman said: "I'm part of a group which is here to represent the rights of unborn babies."
Chief Minister Allan Bell said the legislation was due to be reviewed after the Isle of Man's general election in September.

Wednesday's win for the Asian champions from South Korea means they claim fifth place in Japan ahead of Sundowns.
Kim Bo-kyung, Lee Jong-ho and an own-goal from Ricardo Nascimento gave Jeonbuk a 3-0 lead before half-time.
Percy Tau scored for Sundowns early in the second half before Kim Shin-wook's header sealed the win.
Sundowns lost to Japanese champions Kashima Antlers 2-0 in their other game on their debut at the tournament on Sunday.
Prosecutors are expected to announce on Wednesday whether Conservative politicians or officials will face charges for breaches of expenses rules.
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The chief minister of the Isle of Man has said abortion laws on the island "need changing".
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African Champions League winners Mamelodi Sundowns of South Africa lost again at the Club World Cup going down 4-1 to Jeonbuk Motors in Osaka.